RESUMO
Phenolics and essential oil of peppermint were obtained by pressurized hot water extraction (PHWE). The best extraction conditions were found to be 130 °C for temperature, 10 min for extraction time, and 3 cycles for extraction number. There were no statistically significant differences between 130 and 160 °C in terms of essential oil content. Total phenolic contents (TPC) of the extracts were higher at 160 °C than that of 130 °C. However, further HPLC analysis of the extracts revealed that hydrolysis and/or decomposition of phenolics were observed in the extracts obtained at 160 °C. The main phenolic of peppermint was determined as eriocitrin by HPLC-DAD, while menthol was the dominant component in essential oil fraction of peppermint by GC-FID. The present study demonstrated that PHWE was a suitable technique for simultaneous extraction of phenolics and essential oil from peppermint. The technique might be used as an analytical extraction tool for determination of phenolics and essential oil. Moreover, the extracts of PHWE could directly be evaluated for the enrichment of liquid food formulations or be transformed into solid form by suitable techniques such as spray drying for easy storage and subsequent enrichment of food products.
RESUMO
This study aimed to evaluate the potential effects of choline chloride: glycerol-based natural deep eutectic solvent (NADES) as a plasticizer, NADES extract (NADESext) of lavender as both plasticizer and active ingredient, as well as the lyophilized extract (LE) of lavender at different concentrations (0.5 %, 1 %, and 2 %) on the physical, mechanical, optical, thermal, barrier, morphological, and antioxidant properties of pectin films. The properties of the films were compared to those of the neat pectin film and the film plasticized with glycerol. The addition of plasticizers and LE increased thickness, water vapor permeability, and elongation at break values of the films while decreasing tensile strength and young modulus. Pectin films plasticized with glycerol, NADES, and NADESext had a similar color property but a lower opacity. The use of LE decreased lightness and increased opacity compared to the films with plasticizers. The addition of plasticizers revealed a smoother surface than neat pectin film while LE triggered the formation of agglomerates on the films. Changes in the FTIR spectra of the films showed some interactions between pectin and polyphenols in LE. The plasticizers had an insignificant effect on the antioxidant capacity of films whereas LE improved antioxidant capacity depending on the concentration. In conclusion, the results suggested that pectin films with NADES and LE could be beneficially used to improve antioxidant packaging technology along with acceptable mechanical properties.
RESUMO
The aim of this study was to produce ready to drink (RTD) iced teas from sage and linden. For this purpose, phenolics of sage and linden were extracted by pressurized hot water extraction (PHWE) and then the extracts obtained were spray dried by the addition of maltodextrin. The powders produced by spray drying were processed into RTD sage and linden iced teas by adding sucrose and citric acid. The optimum conditions of PHWE of sage and linden were at 160 °C and for 10 min and 5 min, respectively. The solubility and microencapsulation efficiency of spray dried powders were found to be greater than 97%. In addition, total phenolic content and antioxidant activity of RTD iced teas are parallel with those of microencapsulated sage and linden powders after pasteurization at 80 °C for 5 min. The sensory analysis of RTD iced teas showed that products were well-accepted by the panelists.